Environmental conditions such as temperature, strain, cracks, gross deformations, delamination of composites, wear, acceleration, vibration, sound, corrosion, electric field, magnetic field, moisture, ice deposition, conductivity, permittivity, permeability, and other related characteristics can be measured using known sensors. Most known sensors for monitoring environmental conditions generally require a close connection to processing and display equipment to retrieve measurement information. This connection could be a mechanical connection, a physical electrical conductor connection, or a very short range inductive connection.
Known sensors that do not require such close connections for measuring these environmental characteristics generally involve associated difficulties that reduce their effectiveness. Examples of such known sensors and the difficulties associated therewith follow. A laser measurement system generally is expensive and requires a direct line-of-sight to the environment to be measured. An X-ray or nuclear magnetic resonance imaging system generally is expensive, is of significant size and weight, and requires significant processing time for film or data. An ultrasonic measurement system requires an acoustically-conductive medium. A sensor having an active power source and transmitter generally is bulky, and weighs and costs a significant amount.